Harrison Spinks Quilted Fusion 4000 Pocket Mattress
Mattress
Harrison Spinks Quilted Fusion 4000 Pocket Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Eco-Friendly
Depth (cm)
25
Layers
5
Layer Details
- Quilted panel sleep surface. A quilted panel with tufting hidden on the inside of the soft fabric cover, which means a smooth sleep surface without the knots or bumps you sometimes feel through traditionally tufted mattresses.
- Enviropad filling. Three thick, fluffy layers of Enviropad filling relieve pressure build-up around your hips and shoulders. It's also fully recyclable, so the comfort layer doesn't end up in landfill.
- Cortec™ Quad pocket spring core. The main Cortec Quad core places each spring in its own fabric pocket, secured together without glue. That means each spring moves independently, giving personalised support where your body needs it.
- Posturfil mini pocket springs. 1000 Posturfil mini pocket springs add a bouncy, comforting feel on top of the core. They also improve airflow through the mattress, which helps if you tend to sleep warm.
- HD mini pocket springs. A further 2500 HD mini pocket springs provide additional bouncy comfort. This second mini spring layer is a large part of why the firm feel doesn't come across as harsh.
- .
Layer details from mattressonline.co.uk product page, September 2026.
- Fits most UK bedrooms: At 135 x 190cm it leaves space for bedside tables on both sides in an average room, which a UK king often won't.
- Sensible space for two: You get 67.5cm each for two people sharing, enough for most couples who like sleeping close rather than on separate islands.
- Less partner disturbance: The pocket springs move independently in their own fabric pockets, so one of you turning over is less likely to wake the other.
- Firm support across the whole surface: The 4000-spring construction responds to each sleeper's weight separately, which matters when two differently built people share one mattress.
- Easy to dress: Standard double sheets and a 200 x 200cm duvet are sold everywhere, so there's no hunting for odd-sized bedding.
This size suits you if...
You share the bed every night and want the traditional couples' size in a room that suits it, or you sleep alone and like room to spread out, perhaps with a dog or cat claiming a corner. It also suits a guest room that regularly hosts visiting couples, since the firm feel supports a wide range of body types.
Consider another size if...
Your bedroom comfortably clears 2.7m x 2.9m and you both want more sleeping space. We'd recommend the UK king instead, which is 15cm wider and 10cm longer than the UK double.
Similar Mattresses in This Price Range
Did you know? On Mattress Unboxed we have over 1,000 different mattresses to suit all types of sleepers. View all mattresses.
Is the Quilted Fusion 4000 UK double big enough for a couple?
For most couples, yes. Two people sharing get 67.5cm each, which suits partners who sleep fairly close. If one of you is broad-shouldered or a restless sleeper, the firm surface helps keep you supported at the edges, though couples who want real separation tend to prefer the UK king.
What room size do I need for the Quilted Fusion 4000 in a UK double?
We suggest allowing at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That leaves walking space on both sides and, in most rooms, room for bedside tables too. This guidance is ours rather than Harrison Spinks', so measure your own layout before ordering.
What are the dimensions of the Quilted Fusion 4000 in a UK double?
The UK double measures 135 x 190cm, or 4ft 6in x 6ft 3in, and the mattress is 25cm deep. That footprint fits comfortably in rooms where a UK king would dominate, which is a large part of why the double remains the standard shared size in UK homes.
How much bigger is the UK king than this UK double?
The UK double is 15cm narrower and 10cm shorter than the UK king. That extra width matters most to couples, while the extra length helps taller sleepers. Sizing up needs the room to match: we suggest at least 2.7m x 2.9m for the UK king, against 2.6m x 2.8m for the UK double.
Will the UK double work for two sleepers of different weights?
It's a reasonable match. Each of the 4000 springs sits in its own fabric pocket and moves independently, so a heavier partner sinking in on one side shouldn't tilt the other. The firm feel does mean lighter side sleepers may find it a little solid, and on a shared double there's no soft-side compromise available.